Prime on the product symbol
The amsmath
package has a \sideset
command for this purpose:
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{equation*}
\sideset{}{'}\prod_{n=-k}^k \frac{a_n}{n}
\end{equation*}
\end{document}
The general syntax is
\sideset{_a^b}{_c^d}\sum
producing
and works on any large operator \prod
, \sum
, etc.
You have to detach the superscript from the operator. Below I've inserted a \vphantom
that is the size of \prod
:
\documentclass{article}
\begin{document}
\[
\prod_{i=0}^n f_i \quad \prod{\vphantom\prod}'
\]
\end{document}